From b1e6b7068f026e88257c20522555c78122e5a14d Mon Sep 17 00:00:00 2001 From: Shreshtha Kumar Sahu Date: Tue, 22 Mar 2011 16:30:16 -0700 Subject: [PATCH] leds: add driver for LM3530 ALS Simple backlight driver for National Semiconductor LM3530. Presently only manual mode is supported, PWM and ALS support to be added. Signed-off-by: Shreshtha Kumar Sahu Cc: Linus Walleij Cc: Richard Purdie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/leds/Kconfig | 10 + drivers/leds/Makefile | 1 + drivers/leds/leds-lm3530.c | 378 +++++++++++++++++++++++++++++++++++++ include/linux/led-lm3530.h | 107 +++++++++++ 4 files changed, 496 insertions(+) create mode 100644 drivers/leds/leds-lm3530.c create mode 100644 include/linux/led-lm3530.h diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 6f190f4cdbc0..9bec8699b8a3 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -34,6 +34,16 @@ config LEDS_ATMEL_PWM This option enables support for LEDs driven using outputs of the dedicated PWM controller found on newer Atmel SOCs. +config LEDS_LM3530 + tristate "LCD Backlight driver for LM3530" + depends on LEDS_CLASS + depends on I2C + help + This option enables support for the LCD backlight using + LM3530 ambient light sensor chip. This ALS chip can be + controlled manually or using PWM input or using ambient + light automatically. + config LEDS_LOCOMO tristate "LED Support for Locomo device" depends on LEDS_CLASS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index aae6989ff6b6..39c80fca84d2 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -9,6 +9,7 @@ obj-$(CONFIG_LEDS_88PM860X) += leds-88pm860x.o obj-$(CONFIG_LEDS_ATMEL_PWM) += leds-atmel-pwm.o obj-$(CONFIG_LEDS_BD2802) += leds-bd2802.o obj-$(CONFIG_LEDS_LOCOMO) += leds-locomo.o +obj-$(CONFIG_LEDS_LM3530) += leds-lm3530.o obj-$(CONFIG_LEDS_MIKROTIK_RB532) += leds-rb532.o obj-$(CONFIG_LEDS_S3C24XX) += leds-s3c24xx.o obj-$(CONFIG_LEDS_AMS_DELTA) += leds-ams-delta.o diff --git a/drivers/leds/leds-lm3530.c b/drivers/leds/leds-lm3530.c new file mode 100644 index 000000000000..e7089a1f6cb6 --- /dev/null +++ b/drivers/leds/leds-lm3530.c @@ -0,0 +1,378 @@ +/* + * Copyright (C) 2011 ST-Ericsson SA. + * Copyright (C) 2009 Motorola, Inc. + * + * License Terms: GNU General Public License v2 + * + * Simple driver for National Semiconductor LM3530 Backlight driver chip + * + * Author: Shreshtha Kumar SAHU + * based on leds-lm3530.c by Dan Murphy + */ + +#include +#include +#include +#include +#include +#include +#include + +#define LM3530_LED_DEV "lcd-backlight" +#define LM3530_NAME "lm3530-led" + +#define LM3530_GEN_CONFIG 0x10 +#define LM3530_ALS_CONFIG 0x20 +#define LM3530_BRT_RAMP_RATE 0x30 +#define LM3530_ALS_ZONE_REG 0x40 +#define LM3530_ALS_IMP_SELECT 0x41 +#define LM3530_BRT_CTRL_REG 0xA0 +#define LM3530_ALS_ZB0_REG 0x60 +#define LM3530_ALS_ZB1_REG 0x61 +#define LM3530_ALS_ZB2_REG 0x62 +#define LM3530_ALS_ZB3_REG 0x63 +#define LM3530_ALS_Z0T_REG 0x70 +#define LM3530_ALS_Z1T_REG 0x71 +#define LM3530_ALS_Z2T_REG 0x72 +#define LM3530_ALS_Z3T_REG 0x73 +#define LM3530_ALS_Z4T_REG 0x74 +#define LM3530_REG_MAX 15 + +/* General Control Register */ +#define LM3530_EN_I2C_SHIFT (0) +#define LM3530_RAMP_LAW_SHIFT (1) +#define LM3530_MAX_CURR_SHIFT (2) +#define LM3530_EN_PWM_SHIFT (5) +#define LM3530_PWM_POL_SHIFT (6) +#define LM3530_EN_PWM_SIMPLE_SHIFT (7) + +#define LM3530_ENABLE_I2C (1 << LM3530_EN_I2C_SHIFT) +#define LM3530_ENABLE_PWM (1 << LM3530_EN_PWM_SHIFT) +#define LM3530_POL_LOW (1 << LM3530_PWM_POL_SHIFT) +#define LM3530_ENABLE_PWM_SIMPLE (1 << LM3530_EN_PWM_SIMPLE_SHIFT) + +/* ALS Config Register Options */ +#define LM3530_ALS_AVG_TIME_SHIFT (0) +#define LM3530_EN_ALS_SHIFT (3) +#define LM3530_ALS_SEL_SHIFT (5) + +#define LM3530_ENABLE_ALS (3 << LM3530_EN_ALS_SHIFT) + +/* Brightness Ramp Rate Register */ +#define LM3530_BRT_RAMP_FALL_SHIFT (0) +#define LM3530_BRT_RAMP_RISE_SHIFT (3) + +/* ALS Resistor Select */ +#define LM3530_ALS1_IMP_SHIFT (0) +#define LM3530_ALS2_IMP_SHIFT (4) + +/* Zone Boundary Register defaults */ +#define LM3530_DEF_ZB_0 (0x33) +#define LM3530_DEF_ZB_1 (0x66) +#define LM3530_DEF_ZB_2 (0x99) +#define LM3530_DEF_ZB_3 (0xCC) + +/* Zone Target Register defaults */ +#define LM3530_DEF_ZT_0 (0x19) +#define LM3530_DEF_ZT_1 (0x33) +#define LM3530_DEF_ZT_2 (0x4C) +#define LM3530_DEF_ZT_3 (0x66) +#define LM3530_DEF_ZT_4 (0x7F) + +struct lm3530_mode_map { + const char *mode; + enum lm3530_mode mode_val; +}; + +static struct lm3530_mode_map mode_map[] = { + { "man", LM3530_BL_MODE_MANUAL }, + { "als", LM3530_BL_MODE_ALS }, + { "pwm", LM3530_BL_MODE_PWM }, +}; + +/** + * struct lm3530_data + * @led_dev: led class device + * @client: i2c client + * @pdata: LM3530 platform data + * @mode: mode of operation - manual, ALS, PWM + */ +struct lm3530_data { + struct led_classdev led_dev; + struct i2c_client *client; + struct lm3530_platform_data *pdata; + enum lm3530_mode mode; +}; + +static const u8 lm3530_reg[LM3530_REG_MAX] = { + LM3530_GEN_CONFIG, + LM3530_ALS_CONFIG, + LM3530_BRT_RAMP_RATE, + LM3530_ALS_ZONE_REG, + LM3530_ALS_IMP_SELECT, + LM3530_BRT_CTRL_REG, + LM3530_ALS_ZB0_REG, + LM3530_ALS_ZB1_REG, + LM3530_ALS_ZB2_REG, + LM3530_ALS_ZB3_REG, + LM3530_ALS_Z0T_REG, + LM3530_ALS_Z1T_REG, + LM3530_ALS_Z2T_REG, + LM3530_ALS_Z3T_REG, + LM3530_ALS_Z4T_REG, +}; + +static int lm3530_get_mode_from_str(const char *str) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(mode_map); i++) + if (sysfs_streq(str, mode_map[i].mode)) + return mode_map[i].mode_val; + + return -1; +} + +static int lm3530_init_registers(struct lm3530_data *drvdata) +{ + int ret = 0; + int i; + u8 gen_config; + u8 als_config = 0; + u8 brt_ramp; + u8 als_imp_sel = 0; + u8 brightness; + u8 reg_val[LM3530_REG_MAX]; + struct lm3530_platform_data *pltfm = drvdata->pdata; + struct i2c_client *client = drvdata->client; + + gen_config = (pltfm->brt_ramp_law << LM3530_RAMP_LAW_SHIFT) | + ((pltfm->max_current & 7) << LM3530_MAX_CURR_SHIFT); + + if (drvdata->mode == LM3530_BL_MODE_MANUAL || + drvdata->mode == LM3530_BL_MODE_ALS) + gen_config |= (LM3530_ENABLE_I2C); + + if (drvdata->mode == LM3530_BL_MODE_ALS) { + als_config = + (pltfm->als_avrg_time << LM3530_ALS_AVG_TIME_SHIFT) | + (LM3530_ENABLE_ALS) | + (pltfm->als_input_mode << LM3530_ALS_SEL_SHIFT); + + als_imp_sel = + (pltfm->als1_resistor_sel << LM3530_ALS1_IMP_SHIFT) | + (pltfm->als2_resistor_sel << LM3530_ALS2_IMP_SHIFT); + } + + if (drvdata->mode == LM3530_BL_MODE_PWM) + gen_config |= (LM3530_ENABLE_PWM) | + (pltfm->pwm_pol_hi << LM3530_PWM_POL_SHIFT) | + (LM3530_ENABLE_PWM_SIMPLE); + + brt_ramp = (pltfm->brt_ramp_fall << LM3530_BRT_RAMP_FALL_SHIFT) | + (pltfm->brt_ramp_rise << LM3530_BRT_RAMP_RISE_SHIFT); + + brightness = pltfm->brt_val; + + reg_val[0] = gen_config; /* LM3530_GEN_CONFIG */ + reg_val[1] = als_config; /* LM3530_ALS_CONFIG */ + reg_val[2] = brt_ramp; /* LM3530_BRT_RAMP_RATE */ + reg_val[3] = 0x00; /* LM3530_ALS_ZONE_REG */ + reg_val[4] = als_imp_sel; /* LM3530_ALS_IMP_SELECT */ + reg_val[5] = brightness; /* LM3530_BRT_CTRL_REG */ + reg_val[6] = LM3530_DEF_ZB_0; /* LM3530_ALS_ZB0_REG */ + reg_val[7] = LM3530_DEF_ZB_1; /* LM3530_ALS_ZB1_REG */ + reg_val[8] = LM3530_DEF_ZB_2; /* LM3530_ALS_ZB2_REG */ + reg_val[9] = LM3530_DEF_ZB_3; /* LM3530_ALS_ZB3_REG */ + reg_val[10] = LM3530_DEF_ZT_0; /* LM3530_ALS_Z0T_REG */ + reg_val[11] = LM3530_DEF_ZT_1; /* LM3530_ALS_Z1T_REG */ + reg_val[12] = LM3530_DEF_ZT_2; /* LM3530_ALS_Z2T_REG */ + reg_val[13] = LM3530_DEF_ZT_3; /* LM3530_ALS_Z3T_REG */ + reg_val[14] = LM3530_DEF_ZT_4; /* LM3530_ALS_Z4T_REG */ + + for (i = 0; i < LM3530_REG_MAX; i++) { + ret = i2c_smbus_write_byte_data(client, + lm3530_reg[i], reg_val[i]); + if (ret) + break; + } + + return ret; +} + +static void lm3530_brightness_set(struct led_classdev *led_cdev, + enum led_brightness brt_val) +{ + int err; + struct lm3530_data *drvdata = + container_of(led_cdev, struct lm3530_data, led_dev); + + switch (drvdata->mode) { + case LM3530_BL_MODE_MANUAL: + + /* set the brightness in brightness control register*/ + err = i2c_smbus_write_byte_data(drvdata->client, + LM3530_BRT_CTRL_REG, brt_val / 2); + if (err) + dev_err(&drvdata->client->dev, + "Unable to set brightness: %d\n", err); + break; + case LM3530_BL_MODE_ALS: + break; + case LM3530_BL_MODE_PWM: + break; + default: + break; + } +} + + +static ssize_t lm3530_mode_set(struct device *dev, struct device_attribute + *attr, const char *buf, size_t size) +{ + int err; + struct i2c_client *client = container_of( + dev->parent, struct i2c_client, dev); + struct lm3530_data *drvdata = i2c_get_clientdata(client); + int mode; + + mode = lm3530_get_mode_from_str(buf); + if (mode < 0) { + dev_err(dev, "Invalid mode\n"); + return -EINVAL; + } + + if (mode == LM3530_BL_MODE_MANUAL) + drvdata->mode = LM3530_BL_MODE_MANUAL; + else if (mode == LM3530_BL_MODE_ALS) + drvdata->mode = LM3530_BL_MODE_ALS; + else if (mode == LM3530_BL_MODE_PWM) { + dev_err(dev, "PWM mode not supported\n"); + return -EINVAL; + } + + err = lm3530_init_registers(drvdata); + if (err) { + dev_err(dev, "Setting %s Mode failed :%d\n", buf, err); + return err; + } + + return sizeof(drvdata->mode); +} + +static DEVICE_ATTR(mode, 0644, NULL, lm3530_mode_set); + +static int __devinit lm3530_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct lm3530_platform_data *pdata = client->dev.platform_data; + struct lm3530_data *drvdata; + int err = 0; + + if (pdata == NULL) { + dev_err(&client->dev, "platform data required\n"); + err = -ENODEV; + goto err_out; + } + + /* BL mode */ + if (pdata->mode > LM3530_BL_MODE_PWM) { + dev_err(&client->dev, "Illegal Mode request\n"); + err = -EINVAL; + goto err_out; + } + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + dev_err(&client->dev, "I2C_FUNC_I2C not supported\n"); + err = -EIO; + goto err_out; + } + + drvdata = kzalloc(sizeof(struct lm3530_data), GFP_KERNEL); + if (drvdata == NULL) { + err = -ENOMEM; + goto err_out; + } + + drvdata->mode = pdata->mode; + drvdata->client = client; + drvdata->pdata = pdata; + drvdata->led_dev.name = LM3530_LED_DEV; + drvdata->led_dev.brightness_set = lm3530_brightness_set; + + i2c_set_clientdata(client, drvdata); + + err = lm3530_init_registers(drvdata); + if (err < 0) { + dev_err(&client->dev, "Register Init failed: %d\n", err); + err = -ENODEV; + goto err_reg_init; + } + + err = led_classdev_register((struct device *) + &client->dev, &drvdata->led_dev); + if (err < 0) { + dev_err(&client->dev, "Register led class failed: %d\n", err); + err = -ENODEV; + goto err_class_register; + } + + err = device_create_file(drvdata->led_dev.dev, &dev_attr_mode); + if (err < 0) { + dev_err(&client->dev, "File device creation failed: %d\n", err); + err = -ENODEV; + goto err_create_file; + } + + return 0; + +err_create_file: + led_classdev_unregister(&drvdata->led_dev); +err_class_register: +err_reg_init: + kfree(drvdata); +err_out: + return err; +} + +static int __devexit lm3530_remove(struct i2c_client *client) +{ + struct lm3530_data *drvdata = i2c_get_clientdata(client); + + device_remove_file(drvdata->led_dev.dev, &dev_attr_mode); + led_classdev_unregister(&drvdata->led_dev); + kfree(drvdata); + return 0; +} + +static const struct i2c_device_id lm3530_id[] = { + {LM3530_NAME, 0}, + {} +}; + +static struct i2c_driver lm3530_i2c_driver = { + .probe = lm3530_probe, + .remove = lm3530_remove, + .id_table = lm3530_id, + .driver = { + .name = LM3530_NAME, + .owner = THIS_MODULE, + }, +}; + +static int __init lm3530_init(void) +{ + return i2c_add_driver(&lm3530_i2c_driver); +} + +static void __exit lm3530_exit(void) +{ + i2c_del_driver(&lm3530_i2c_driver); +} + +module_init(lm3530_init); +module_exit(lm3530_exit); + +MODULE_DESCRIPTION("Back Light driver for LM3530"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Shreshtha Kumar SAHU "); diff --git a/include/linux/led-lm3530.h b/include/linux/led-lm3530.h new file mode 100644 index 000000000000..bb69d20da0dc --- /dev/null +++ b/include/linux/led-lm3530.h @@ -0,0 +1,107 @@ +/* + * Copyright (C) 2011 ST-Ericsson SA. + * Copyright (C) 2009 Motorola, Inc. + * + * License Terms: GNU General Public License v2 + * + * Simple driver for National Semiconductor LM35330 Backlight driver chip + * + * Author: Shreshtha Kumar SAHU + * based on leds-lm3530.c by Dan Murphy + */ + +#ifndef _LINUX_LED_LM3530_H__ +#define _LINUX_LED_LM3530_H__ + +#define LM3530_FS_CURR_5mA (0) /* Full Scale Current */ +#define LM3530_FS_CURR_8mA (1) +#define LM3530_FS_CURR_12mA (2) +#define LM3530_FS_CURR_15mA (3) +#define LM3530_FS_CURR_19mA (4) +#define LM3530_FS_CURR_22mA (5) +#define LM3530_FS_CURR_26mA (6) +#define LM3530_FS_CURR_29mA (7) + +#define LM3530_ALS_AVRG_TIME_32ms (0) /* ALS Averaging Time */ +#define LM3530_ALS_AVRG_TIME_64ms (1) +#define LM3530_ALS_AVRG_TIME_128ms (2) +#define LM3530_ALS_AVRG_TIME_256ms (3) +#define LM3530_ALS_AVRG_TIME_512ms (4) +#define LM3530_ALS_AVRG_TIME_1024ms (5) +#define LM3530_ALS_AVRG_TIME_2048ms (6) +#define LM3530_ALS_AVRG_TIME_4096ms (7) + +#define LM3530_RAMP_TIME_1ms (0) /* Brigtness Ramp Time */ +#define LM3530_RAMP_TIME_130ms (1) /* Max to 0 and vice versa */ +#define LM3530_RAMP_TIME_260ms (2) +#define LM3530_RAMP_TIME_520ms (3) +#define LM3530_RAMP_TIME_1s (4) +#define LM3530_RAMP_TIME_2s (5) +#define LM3530_RAMP_TIME_4s (6) +#define LM3530_RAMP_TIME_8s (7) + +/* ALS Resistor Select */ +#define LM3530_ALS_IMPD_Z (0x00) /* ALS Impedence */ +#define LM3530_ALS_IMPD_13_53kOhm (0x01) +#define LM3530_ALS_IMPD_9_01kOhm (0x02) +#define LM3530_ALS_IMPD_5_41kOhm (0x03) +#define LM3530_ALS_IMPD_2_27kOhm (0x04) +#define LM3530_ALS_IMPD_1_94kOhm (0x05) +#define LM3530_ALS_IMPD_1_81kOhm (0x06) +#define LM3530_ALS_IMPD_1_6kOhm (0x07) +#define LM3530_ALS_IMPD_1_138kOhm (0x08) +#define LM3530_ALS_IMPD_1_05kOhm (0x09) +#define LM3530_ALS_IMPD_1_011kOhm (0x0A) +#define LM3530_ALS_IMPD_941Ohm (0x0B) +#define LM3530_ALS_IMPD_759Ohm (0x0C) +#define LM3530_ALS_IMPD_719Ohm (0x0D) +#define LM3530_ALS_IMPD_700Ohm (0x0E) +#define LM3530_ALS_IMPD_667Ohm (0x0F) + +enum lm3530_mode { + LM3530_BL_MODE_MANUAL = 0, /* "man" */ + LM3530_BL_MODE_ALS, /* "als" */ + LM3530_BL_MODE_PWM, /* "pwm" */ +}; + +/* ALS input select */ +enum lm3530_als_mode { + LM3530_INPUT_AVRG = 0, /* ALS1 and ALS2 input average */ + LM3530_INPUT_ALS1, /* ALS1 Input */ + LM3530_INPUT_ALS2, /* ALS2 Input */ + LM3530_INPUT_CEIL, /* Max of ALS1 and ALS2 */ +}; + +/** + * struct lm3530_platform_data + * @mode: mode of operation i.e. Manual, ALS or PWM + * @als_input_mode: select source of ALS input - ALS1/2 or average + * @max_current: full scale LED current + * @pwm_pol_hi: PWM input polarity - active high/active low + * @als_avrg_time: ALS input averaging time + * @brt_ramp_law: brightness mapping mode - exponential/linear + * @brt_ramp_fall: rate of fall of led current + * @brt_ramp_rise: rate of rise of led current + * @als1_resistor_sel: internal resistance from ALS1 input to ground + * @als2_resistor_sel: internal resistance from ALS2 input to ground + * @brt_val: brightness value (0-255) + */ +struct lm3530_platform_data { + enum lm3530_mode mode; + enum lm3530_als_mode als_input_mode; + + u8 max_current; + bool pwm_pol_hi; + u8 als_avrg_time; + + bool brt_ramp_law; + u8 brt_ramp_fall; + u8 brt_ramp_rise; + + u8 als1_resistor_sel; + u8 als2_resistor_sel; + + u8 brt_val; +}; + +#endif /* _LINUX_LED_LM3530_H__ */ -- 2.20.1